Naloxone, a drug used to treat narcotic overdoses in emergencies, was administered to relieve the symptoms.

The slew of overdoses comes as the Centers for Disease Control (CDC) published a preliminary report on Wednesday on the record number of American drug deaths.

According to the estimates, drugs - particularly fentanyl - are now deadlier in the US than HIV, car crashes and guns.

Synthetic opiates like fentanyl, which is 30-50 times more potent than heroin, are extremely dangerous.

Just 2mg of fentanyl - the equivalent of a few grains of table salt - is a lethal dosage for most people, and even exposure can cause a fatal reaction, according to the Drug Enforcement Administration (DEA).

Fentanyl is approved as an anaesthetic and for pain relief, but its high profit margin for traffickers has made it a key drug in the US opioid crisis.

The CDC reported that between 2015 and 2016, the rate of drug overdose deaths in the US involving synthetic opioids such as fentanyl had doubled.

In New Haven, Fire Chief John Alston Jr told reporters the opiate problem is a far-reaching one.

"People are self-medicating for several different reasons and every agency - police, fire, medical, hospitals - all are strained at this time," Chief Alston said.